My internet connection frequently stops working (I can't open any websites, ping does not work, online games disconnect, etc.) but my WiFi is still connected. I've only installed Ubuntu a few days ago, so I might just have noticed the problem now. I've also checked, that my other devices have a working internet connection, so I'm sure the problem isn't with my router.
output of the wireless info script
EDIT:
- the problem occurs more than once per hour
- disconnecting from and reconnecting to WiFi temporarily fixes the problem 
- rebooting the router does not fix the problem 
- other devices are unaffected
- turning off power management does not fix the problem
- lshw output
- The problem does not occur on Windows(dual-boot)
- fixing the routers WiFi channel does not fix the problem